#include <iostream>
using namespace std;

class Base {
public:
	int m_public;
};
class Derived:protected Base {};

int main (void)
{
	Derived d;
	//变成保护成员, 向上造型直接报错
	//Base *pb = &d;
	//Base *pb = static_cast <Base*> (&d);
	Base *pb = (Base*) (&d);

	return 0;
}
